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911.
From the mathematical studies, the conservative relationships of the depth integral areas of the linear well logs and the
nonlinear well logs are derived: the depth integral area of a linear well log is not relevant to its vertical resolution,
while the depth integral area of a nonlinear well log is closely related to its vertical resolution and the higher the resolution,
the bigger the depth integral area. Then, the effects of the mathematical transformations on the above relationships are studied.
Finally, the conservative relationships of the shale volume content log and the porosity log are derived for some given conditions.
Project supported by the National Natural Science Foundation of China (Grant No. 49200-400). 相似文献
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914.
The influence of carbonate formation on Pulsed Neutron logging(such as Pulsed Neutron-Neutron logging)is quite different from that of sandstone due to the complexity of reservoir architecture and the development of fracture in carbonate reservoir.To study the factors affecting Pulsed Neutron-Neutron(PNN)logging in carbonate formation,the responses on fracture or cave are simulated by Monte Carlo method,getting the relationships among the macroscopic capture cross section(Σ),the count ratio of the thermal neutron at far spacing and near spacing detectors(RATIO),the fracture porosity,oil-bearing and shale content of fracture.The results show that PNN logging can be used to detect caves,and there exist linear relationships among the macroscopic capture cross section(Σ),the count ratio(RATIO)and the above factors.The research findings in this paper provides theoretical basis for the interpretation and data correction of the PNN logging in carbonate reservoirs. 相似文献
915.
CO2气藏由于其物理、化学性质的特殊性,CO2气勘探与烃类气既有相同又有区别,综合应用多种资料和多种技术方法是识别CO2气(层)藏的有效手段。利用区域地质分析、地球物理和地球化学勘探方法综合评价非烃气的分布,提出钻探目标,通过非烃色谱测量法和红外线CO2气体浓度测量法实现CO2气层钻井现场动态检测,利用气体色谱检测相关录井参数资料、核测井密度中子孔隙度差值综合解释CO2气层,有效地识别CO2气。主要介绍CO2气藏综合勘探技术的关键的新技术方法,如地球化学方法、录井和测井综合识别的关键技术方法等。 相似文献
916.
支持向量机在水淹层测井识别中的应用 总被引:2,自引:1,他引:1
支持向量机(SVM)算法是特别适合于用有限已知样本训练建模,进而预报未知样本属性的模式识别新算法。笔者尝试将Vapnik提出的支持向量机算法用于水淹层测井识别。总结了P油田水淹层的声波时差、自然电位、深感应电阻率、中感应电阻率及密度测井曲线与水淹程度的对应关系,建立了基于支持向量分类机的识别模型,并将上述参数作为训练样本的输入,油气特征作为训练样本的输出,对支持向量机进行训练。对于P油田水淹层的实际预测结果表明:支持向量机可以成为一种用于水淹层识别的有效工具。 相似文献
917.
Road building in Congo Basin forests has increased due to expansion of commercial logging, with potential to expose intact forests to greater establishment of agriculture. We developed new knowledge of agriculture clearing sizes, spatial patterns, and relationships with roads in seven case study sites comprising 7,529 km2. Using very high spatial resolution satellite imagery, we mapped roads and rivers, plus clearings for agriculture, settlements, and logging. Mapped clearings (N = 1,781) ranged in size from 0.008 ha to more than 300 ha; most were smallholder agriculture, with 64 percent ≤ 1 ha. Statistical tests of spatial pattern confirmed that agriculture occurred in an inhomogeneous-aggregated pattern, suggesting interactions with other landscape elements. Proximity analyses showed that 76 percent of clearings were within 1 km of a road or river. Thirty-five percent of agriculture clearings were within 1 km of main public roads built before 1990, compared to 17 percent for logging roads built after 2000. Less than 6 percent of agriculture clearings were within 1 km of logging roads with overgrown canopies, suggesting transient relationships. Results based on fine-scale data provide new empirical support for understanding the interactions between agriculture and roads in one of the remaining relatively intact forest areas of the Congo Basin. 相似文献
918.
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920.
In a general treatment of the theory of induction logging, an exact integral representation has been obtained for the mutual impedance between a vertical dipole transmitter and a coaxial dipole receiver in a three layered earth. Based on this representation, a computer model has been devised using the traditional Slingram system of induction logging and the comparatively new Turam system, ignoring borehole effects. The model results indicate that due to its much larger response, the Turam system is in general preferable to the Slingram in mineral and groundwater investigations where formation conductivity much less than 1 S/m is generally encountered. However, if the surrounding media are conductive (more than 0.1 S/m), the Turam system suffers from large amplitude attenuation and phase rotation of the primary field caused by the conductive surrounding, and is less useful than the Slingram system which does not so suffer, unless the target bed is shallow. Because it is a more complex function of system parameters than the corresponding Slingram log, a Turam log can be conveniently interpreted only by the modern inverse method using a fast algorithm for the forward solution and a high speed digital computer. 相似文献